The word “irruption” from the Latin “irrumpere” means to break in or enter forcibly or suddenly. For example, one might say that absurdities continually irrupt into the Alturas Lake ski report. It can also refer to the migration into an area by birds or animals in unusually large numbers. For example, on occasion, there may be an irruption of  Hawk Owls from the realm of the Northern Lights into the mountains of central Idaho or on presidents’ day weekend we sometimes see an almost Malthusian irruption of human skiers and general partygoers into the Sawtooth Valley . Don’t miss out on the fun under the sun at the Alturas Lake ski area where, on Saturday, the Trail to Lake, Over the Hill, Sheep Thrills and South Loop were groomed  for skate and classic skiers.